Flyable model rocket

ABSTRACT

A model rocket is provided by the use of a printer to print markings on a substrate so as to enable a user to separate the various components of the model rocket from the substrate. The user can then assemble these substrate pieces in order to create a flyable model rocket. The opportunity is provided for the model rocket enthusiast to interactively participate in the design aspects of the model rocket activity, suitable for use in an educational environment, such as a classroom. The model rockets may be combined with readily commercially available model rocket engines, and optionally engine tubes and other components. Furthermore, according to one implementation, the model rocket may be viewed on a computer display prior to constructing the model rocket. Estimates may also be determined by a computer for the anticipated flight of the model rocket.

TECHNICAL FIELD

[0001] This invention relates to model rocketry generally. Specifically, the invention relates to flyable model rockets printed on a substantially planar substrate which can thereafter be assembled into three-dimensional form by a user.

BACKGROUND

[0002] Model rocketry in the United States began in approximately 1957. Model rocketry is enjoyed by a wide variety of people and can be used as a tool to teach topics such as physics and principles of flight. People can participate in model rocketry at different levels. For example, model rocketry manufacturers provide kits of pre-manufactured components that are assembled before the model rocket is flown. An example of a model rocket kit can be found in U.S. Pat. No. 5,267,885 to Niskern, et al.

[0003] Others participate in model rocketry by purchasing some components from a manufacturer, such as model rocket engines, launch equipment, or portions of the model rocket. Some users choose to fabricate some or all of the components for assembly or launch of their model rocket.

[0004] Still others participate in model rocketry by making non-flyable models. Some model rockets are for display only and are not capable of being mounted with a model rocket engine or withstand a flight.

SUMMARY

[0005] A model rocket is provided by the use of a printer to print markings on a substrate so as to enable a user to separate the various components of the model rocket from the remaining part of the substrate, such as by cutting substrate pieces out of the substrate. The user can then assemble these substrate pieces in order to create a flyable model rocket. The substrate may be a substantially planar product, such as paper or card stock.

[0006] The opportunity is provided for the model rocket enthusiast to interactively participate in designing their model rocket. It is suitable for use in an educational environment, such as a classroom. The resulting model rockets may be combined with commercially available model rocket engines, and optionally with engine tubes and other components such as modeling clay, shock cords and launch equipment. According to one implementation, the model rocket may be interactively viewed on a computer display prior to printing and constructing the model rocket. Estimates may also be determined by a computer for the anticipated flight of the proposed model rocket design.

[0007] According to one embodiment of the invention, a flyable model rocket is provided having a nose cone formed of at least one substrate piece. A fuselage is provided which may be removably mounted to the nose cone. A tail assembly is fixedly mounted to the fuselage and formed of at least two substrate pieces. A first substrate piece of the tail assembly and a second substrate piece of the tail assembly form a tail assembly fin at a location where the first substrate piece of the tail assembly meets the second substrate piece of the tail assembly.

[0008] According to another embodiment of the invention, a flyable model rocket includes a nose cone formed of at least two substrate pieces, wherein a first substrate piece of the nose cone forms a nose cone fin. Other nose cone fins may be similarly formed. The nose cone fin is located where the first substrate piece of the nose cone meets a second substrate piece of the nose cone. A fuselage, also formed of one or more substrate pieces, may be removably mounted to the nose cone. A tail assembly is formed of at least two substrate pieces, wherein a first substrate piece of said tail assembly and a second substrate piece of said tail assembly form a tail assembly fin at a location where the first substrate piece of the tail assembly meets the second substrate piece of the tail assembly.

[0009] According to a further embodiment of the invention, a flyable model rocket has a nose cone formed of a printed substrate and a tail assembly formed of a printed substrate. The tail assembly is removably directly mated to the nose cone and adapted to be mounted to a model rocket engine.

[0010] Another embodiment of the invention provides a flyable model rocket having at least one nose cone fin. The flyable model rocket includes a nose cone formed of three substrate pieces, wherein a first substrate piece of the nose cone forms a nose cone fin at a location where the first substrate piece of the nose cone meets a second substrate piece of the nose cone. Other nose cone fins may be similarly formed. A tail assembly is formed of three substrate pieces, wherein a first substrate piece of the tail assembly forms a tail assembly fin at a location where the first substrate piece of the tail assembly meets a second substrate piece of the nose cone. Other tail assembly fins may be similarly formed.

[0011] Various other embodiments of the invention are described herein by way of example and include methods of constructing a flyable model rocket, a computer readable medium and a flyable model rocket assembly kit.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The invention will be apparent from the description herein and the accompanying drawings, in which like reference characters refer to the same parts throughout the different views.

[0013]FIG. 1 illustrates an exploded view of a conventional model rocket;

[0014]FIG. 2 illustrates a perspective view of a model rocket according to an embodiment of the invention;

[0015]FIG. 3 illustrates another perspective view of the model rocket shown in FIG. 2 with the nose cone removed;

[0016]FIG. 4 illustrates a stiffener in relation to an engine tube according to an example of an implementation of the invention;

[0017]FIG. 5 illustrates a substrate piece according to an embodiment of the invention;

[0018]FIG. 6 illustrates a model rocket according to a second embodiment of the invention;

[0019]FIG. 7 is a perspective view of the model of FIG. 6, showing the nose cone removed;

[0020]FIG. 8 is an example of a substrate according to an implementation of the invention;

[0021]FIG. 9 is a perspective view of a model rocket according to a third embodiment of the invention;

[0022]FIG. 10 illustrates a further view of the model rocket of FIG. 9, showing the nose cone removed;

[0023]FIG. 11 illustrates a method according to a further embodiment of the invention;

[0024]FIG. 12 illustrates a computer-readable medium according to a further embodiment of the invention; and

[0025]FIG. 13 illustrates a flyable model rocket assembly kit according to a further embodiment of the invention.

DETAILED DESCRIPTION

[0026] The present invention provides an opportunity for the model rocket user to be actively involved in the design and configuration of the model rocket. The invention enables the use of a printer to print markings on a substrate so as to enable a user to produce the various components of the model rocket from the substrate. The printed markings can include guides to aid the user in separating the components from the substrate, such as lines to aid a user in cutting the components from the substrate and folding the component for the desired component shape. Printed markings can also include graphical enhancements to the model rocket, such as colors, and other indicia to simulate rocket components, such as windows, door hatches and identification numbers. The user can then assemble these components formed of substrate pieces to create a flyable model rocket. A computer readable medium is provided according to an embodiment of the invention to receive instructions specifying various characteristics of the model rocket. This enables the user to interactively provide input to develop and design the model rocket.

[0027] The present invention is well suited to use in an educational environment, such as a classroom. Various embodiments of the present invention may be used to provide students with the ability to design a unique rocket distinct from those of their classmates, while still providing a safe and successful model rocket launch for members of the class. Various embodiments of the invention may also be used with a corresponding curriculum in order to teach students about the principles of flight and the functions of the various components of the model rocket.

[0028] For purposes of illustration, a conventional model rocket 100 is shown in FIG. 1. A body tube 110 is typically provided to be coupled with fins 120 and a nose 130. The body tube 110 may be formed of multi-layered paper, cardboard, fiberglass, paper or plastic. The nose 130 is typically formed of wood, plastic or fiberglass, and the fins 120 are typically formed of plastic, wood, cardstock or fiberglass. Examples of the fins include injection molded plastic fins or vacuum-formed plastic fins. Usually fins are made of ABS plastic and may also be high-impact styrene or a polycarbonate plastic.

[0029] A model rocket engine 140 is provided to be located in one end of the body tube 110. An igniter 142 and igniter wadding or an igniter holder 144 are typically used to ignite the model rocket engine 140 when coupled to an electrical power source (not shown).

[0030] A thrust mount 112 is provided inside the body tube 110 for receiving thrust forces of the model rocket engine 140. The model rocket engine 140 is typically located to contact the thrust mount 112. When the nose cone 130 is removable, a cord 150 is typically provided between the nose 130 and the body tube 110 so as to keep the nose 130 coupled to the body tube 110. A recovery device 160, such as a streamer, parachute or rotating blades, may be coupled to the body tube 110 and/or nose 130 by the use of the cord 150. The cord 150 may be attached to the body tube 110 by a cord attachment 152, such as tape. Recovery wadding 170 may be provided to enhance the operation of the conventional model rocket 100 by providing a barrier to the heat generated by the model rocket engine 140 during discharge of an ejection thrust. Therefore, the heat reaching the nose 130 and recovery device 160 is reduced.

[0031] In operation, the conventional model rocket 100 is typically mounted to a launch pad (not shown) by locating a rod within the launch lug 114 on the body tube 110. The model rocket engine 140 is ignited, producing a downward thrust that lifts the rocket. A time delay stage of the rocket engine allows the model rocket to continue to climb without additional thrust. After a pre-determined amount of time, the model rocket engine 140 may discharge an ejection thrust into the body tube 110. The ejection force from the model rocket engine 140 is much smaller than the downward thrust used to launch the rocket but is sufficient to dislodge the recovery wadding 170 and the nose 130. Also, the recovery device 160 is dislodged from the body tube 110. The ejection thrust from the model rocket engine 140 is often timed to occur near the apogee of the conventional model rocket 100 flight, allowing the recovery device 160 to be deployed at the beginning of the descent phase of the flight.

[0032] According to one embodiment of the invention, a model rocket 200 is provided as illustrated in FIGS. 2 and 3. The model rocket 200 includes a tail assembly 210, a fuselage 230 and a nose cone 250. As illustrated in FIG. 3, the nose cone 250 is removably mounted to the fuselage 230 while the tail assembly 210 is fixedly mounted to the fuselage 230. A tether 260 may be provided to couple the nose cone 250 to the fuselage 230. The tether 260 may be mounted to the nose cone 250 and fuselage 230, or other part of the model rocket 200 by tether mounts 262.

[0033] The tail assembly 210, in the present example, includes four (4) tail assembly fins 212, 214, 216, 217 each separated by approximately 90 degrees. The tail assembly 210 may be formed by adhering four (4) substrates to each other. For example, each tail assembly fin 212, 214, 216, 217 is preferably formed by mating two (2) substrate pieces to each other, such as by the use of an adhesive. The substrate used to form the tail assembly 210 can be made of a wide variety of substrates that are capable of being cut and folded. One example is card stock or paper, such as readily available paper that may be used in a printer. Although a wide variety of substrate thicknesses may be used, one example uses 85 pound paper substrate in the example model rocket 200. Although the invention is not so limited, another implementation uses 60-85 pound paper stock. Another implementation uses paper stock of less than 120 pounds. As used herein, the term “substrate” refers to a wide variety of substantially planar materials adapted to receive ink from a printer and be cut, bent, creased, and/or curled along one or more lines. Examples include and a variety of papers, card stocks, thin plastic sheets, embossed stock, synthetic stock and adhesive-backed stock. For ease of use in a standard printer, thin plastic sheets may be between 0.010 inches and 0.048 inches thick, although the invention is not so limited. One example of a thin plastic sheet is a heat-resistant acetate, such as transparency sheets capable of use with a high-temperature copier or laser printer. Synthetic stock may include a wide variety of products, one example is TYVEK®, available from E. I. du Pont de Nemours and Company of Wilmington, Del. Adhesive-backed stock may use a wide variety of adhesives, including adhesives designed to make a surface of stock adhere to other objects. 3M Company of St. Paul, Minn. provides a variety of such adhesives.

[0034] Although a wide variety of adhesives may be used, a common white glue, such as ELMER'S GLUE®, a rubber cement, or a fast-drying contact-type glue such as SUPER GLUE® may be used. Other adhesives known in the art, such as Franklin TITEBOND® (available from Franklin International, Columbus, Ohio), carpenter's glue, epoxy, solvent or plastic cement, spray or aerosol adhesive, glue sticks, tape tube-type adhesive and adhesive stock, also may be used. Each substrate piece, such as the exemplary substrate piece 218, is preferably used to form one-half of two (2) tail assembly fins 212, 214, 216, 217. Alternatively, one substrate piece can be used to form both sides of multiple tail assembly fins or both sides of a single tail assembly fin.

[0035] At a location approximately centrally located in the tail assembly 210, each of the substrate pieces, such as exemplary substrate piece 218, may be folded, bent, creased and/or curled to project outward to provide an engine housing 220 to facilitate the insertion of a model rocket engine 222 substantially within the tail assembly 210 or fuselage 230. The model rocket engine 222 may be selected from a wide variety of thrust-producing engines. In one implementation of the invention, a factory-made solid propellant rocket motor is used. An example of such a motor is the Half-A Mini model rocket engine available from Estes-Cox Corporation of Penrose, Colo. The model rocket 200 may further be provided with an engine tube 223. The engine tube 223 may be fixed to the tail assembly 210 or fuselage 230 by an adhesive. The model rocket engine 222 is then located within the engine tube 223, such as by friction or slip-fit. According to one implementation, masking tape may be applied to the outside of the model rocket engine 222 before the model rocket engine 222 is friction or slip-fit into the engine tube 223. Although optional, the masking tape aids in holding the model rocket engine 222 in the engine tube 223, instead of relying only on the friction inherent in the slip-fitting of the model rocket engine 222 in the engine tube 223. The masking tape assists in accommodating the swelling of the model rocket engine 222 caused by atmospheric conditions and operation of the engine. It is understood that further model rocket engine mounting alternatives known in the art are within the scope of the invention. For example, a plastic-type engine mount having a retainer cap or a metal engine hook may be used.

[0036] A model rocket engine 222 may be mounted directly to the substrate pieces of the tail assembly 210 by using an engine tube 223 instead of directly mounting the model rocket engine 222 to the substrate piece within the tail assembly 210. The model rocket 200 may be used for more than one flight more easily in such a case, as the used model rocket engine may be more easily removed from the tail assembly 210. Additionally, the engine tube 223 assists in insulating the tail assembly 210 from the heat generated by the model rocket engine 222.

[0037] A stiffener 224 may optionally be included for one or more of the tail assembly fins 212, 214, 216, 217. The stiffener 224 may be provided to stiffen the tail assembly fins 212, 214, 216, 217 to provide enhanced aerodynamic performance during flight of the model rocket 200 by inhibiting flutter of the tail assembly fins and maintaining the configuration of the fin at high speeds during flight. The stiffener 224 may be glued between the substrate pieces forming each of the tail assembly fins 212, 214, 216, 217 or to an outer surface.

[0038] With reference to FIG. 4, although the invention is not so limited, the stiffener 224 may be formed of an upper component 225 and a lower component 227. The stiffener 224 is shown in relation to an engine tube 223. It is understood that in this illustration, the engine tube 223 may be substituted by a model rocket engine 222. In the illustrated example, the upper component 225 is provided with an engine retention tab 226, although the invention is not so limited. The engine retention tab 226 is located near an upper end of the model rocket engine 222 and/or engine tube 223. The engine retention tab 226 may be provided to assist in transferring the thrust force produced by the model rocket engine 222 to the model rocket 200.

[0039] The illustrated embodiment of the model rocket allows for variations of wing sweep angles. In alternative implementations, sweep angles may be 30°, 45° or 60°, although the invention is not so limited. The lower component 227 may be rotated to be located completely between the substrate pieces of the tail assembly 210, thereby allowing the entire stiffener 224 to be within the tail assembly 210. The upper component 225 may be aligned substantially vertically, so as to be located along an outside surface of the engine tube 223 or model rocket engine 222. A portion of the upper component 225 may also be located between the substrate pieces of the tail assembly 210, allowing adhesive to fixedly locate the upper component 225 relative to the tail assembly 210. In such a configuration, the engine retention tab 226 may assist in retaining the engine tube 223 and/or model rocket engine 222 during flight.

[0040] The stiffener 224 may be formed of a wide variety of materials. Examples include paper, card stock, balsa wood, plastics and STYROFOAM®. In one implementation, the stiffener is formed of 48 point card stock, although the invention is not so limited.

[0041] The tail assembly 210 is configured to be fixedly secured to the fuselage 230. According to one implementation of the invention, the tail assembly 210 may extend into or form a portion of the fuselage 230.

[0042] The fuselage 230 may be fixedly mounted to the tail assembly 210 by the use of an adhesive. According to one implementation of the invention, the fuselage 230 is formed of four (4) substrate pieces 231, forming a square or rectangle in cross-section. According to one implementation of the invention, the substrate piece 231 may be substantially planar. According to one implementation, fuselage fins 232 are formed by extensions of the substrate pieces at the locations where each of the substrate pieces meet. According to another implementation, fuselage fins 232 are affixed to external surfaces of the substrate pieces.

[0043] A launch lug 234 may also be provided to guide the model rocket 200 during its departure from a launch pad. In order to minimize contact between portions of a launch pad guide rod with the model rocket 200 and ease the launch, a launch lug mount 236 may be provided to locate the launch lug 234 several millimeters off the surface of the fuselage 230.

[0044] Each of the four (4) substrate pieces of the fuselage may be assembled by providing each of the substrate pieces with one (1) or more tabs for adhering to neighboring substrate pieces. An example of a tab can be seen in FIG. 5 in which a substrate piece 231 is shown prior to assembly. The substrate piece 231 is shown having flaps 231 a designed to be mated to the back or the front of a neighboring substrate piece 231 during construction of the model rocket 200 such as by the use of an adhesive. Portions of fuselage fins 232 may also be provided to be mated to a neighboring fuselage fin 232.

[0045] According to another implementation, tab and slot construction may be used to couple neighboring substrate pieces to each other. For example, instead of, or in addition to, the use of adhesive to couple a substrate piece to a neighboring substrate piece, the neighboring substrate piece may be provided with a slot for receiving the tab of the other substrate piece, thereby coupling the two substrate pieces together.

[0046] It is understood that variations in design are within the scope of the invention. For example, fuselage fins 232 or nose cone fins 252 may be omitted. In such a case, flap 231 a may be extended along a greater length of the edge of the substrate piece 231. Flaps 231 b may also be provided. If flaps 231 b are provided, they may be folded over to provide a stronger top edge of the fuselage 230.

[0047] The nose cone 250 of model rocket 200 is also constructed of at least one piece of a substrate. The nose cone 250 may be configured to have a similar cross-section than the fuselage 230, to provide for the nose cone 250 to be slip-fit mounted to an upper end of the fuselage 230. In one implementation, the nose cone 250 may be constructed in a similar fashion to the assembly of fuselage 230. In the embodiment illustrated in FIG. 2, a substrate piece 251 of nose cone 250 is provided with a flap to be mated to a neighboring substrate piece 251. As shown in FIG. 2, a flap 251 a from a neighboring substrate piece is shown adhered to the illustrated substrate piece 251. The substrate piece 251 may similarly be adhered to neighboring substrate pieces in such a manner to form a tapered nose cone 250. According to one implementation, ballast 253, such as modeling clay, may be provided in the nose cone 250 in order to locate a center of gravity of the model rocket 200 ahead of a center of pressure occurring during flight. The tether mount 262 may be any item capable of securing the tether 260 to a substrate piece. Examples include adhesive, adhesive tape and a piece of substrate adhered to the substrate piece 251 and the tether 260.

[0048] One or more nose cone fins 252 may be provided with a nose cone 250. The nose cone fins may be formed by extensions of the substrate pieces 251 at locations where the substrate pieces meet, or may be separate pieces affixed to the nosecone 250.

[0049] Optionally, the various components may be die cut or laser cut, stamped or cut by another known manufacturing method or cut by the user. The engine tube 223 may be selected from many commonly available model rocket engine tubes. An example is the Body Tube BT-5 of Estes-Cox Corporation of Penrose, Colo.

[0050] Optionally, the present invention may be used with a manufactured nose cone. For example, the fuselage and/or fin assembly may be provided, as described herein according to any of the embodiments of the invention, and coupled to a nose cone that is known in the art. As described above, examples of nose cones known in the art include those made of wood, plastic or fiberglass, although the invention may be used with any type of nose cone mountable to the fuselage or fin assembly of the invention. According to one implementation the manufactured nose cone is removably mounted to the fuselage or fin assembly. In such a case, a portion of the manufactured nose cone can fit within a portion of the fuselage or fin assembly, and/or may be configured to fit over a portion of the fuselage or fin assembly. Optionally, a tether may be provided to tether the manufactured nose cone to the model rocket. According to another implementation, the manufactured nose cone may be provided to be fixedly mounted to the fuselage or fin assembly. As an example, adhesive may be used to fixedly mount the nose cone to the remainder of the model rocket. An example of an adhesive is a tube-type adhesive.

[0051] According to a second embodiment of the invention, illustrated in FIGS. 6 and 7, the model rocket 300 may be constructed with three (3) tail assembly fins 312, 314, 316. The second embodiment of the invention illustrates various differences that may be employed in the wide variety of designs within the scope of the invention. In this example, the nose cone 350 does not have nose cone fins. Further, the lower edge of the substrate pieces 351 of the nose cone 350 are shaped differently than those of the nose cone 250 of model rocket 200. Also, the fuselage fins 332 are shaped differently than the fuselage fins 232 of the first embodiment. It will be understood that the cross-section of the fuselage 330 and nose cone 350 are triangular to more easily accommodate the three tail assembly fins 312, 314, 316, although the invention is not so limited. It will also be understood that the variations illustrated in FIGS. 6 and 7 may be likewise employed in the embodiments illustrated in FIGS. 2 and 3. The remaining aspects of the model rocket 300 according the illustrated second embodiment are similar to those described above in relation to the model rocket 200 of the first embodiment.

[0052]FIG. 8 illustrates an example of a substrate sheet 201 containing components for an example of a model rocket according to the invention. By the use of two (2) such substrate sheets 201, an example of the model rocket can be assembled. According to one implementation of the invention, a tail assembly having four tail assembly fins 212, 214, 216, 217 may be constructed by using the pieces available on two substrate sheets 201 of FIG. 8. Likewise, using fewer than all of the components on two substrate sheets 201, a three tail assembly fin embodiment of the model rocket may be constructed.

[0053] A third embodiment of the invention is illustrated in FIGS. 9 and 10. According to this embodiment of the invention, a model rocket 400 is illustrated by way of example as having a nose cone 450 and a tail assembly 410 coupled directly to each other. The illustrative example of the model rocket 400 according to the third embodiment of the invention does not include a separate fuselage but may be formed of the combination of the nose cone assembly and the tail fin assembly. According to this embodiment of the invention, the nose cone 450 of the model rocket 400 is provided with one (1) or more nose cone fins 452. According to this embodiment, at least one of the nose cone fins 452 form a mating slot 470 adapted to be coupled with a portion of a tail assembly fin 412, 414, 416, such as by insertion of a portion of the tail assembly fin 412, 414, 416 into the mating slot 470. The launch lug 434 may be provided as illustrated by way of example, or may optionally be mounted on a launch lug mount, as shown in other embodiments. Except as noted herein, the nose cone 450 and tail assembly 410 of this embodiment may be constructed similarly to the nose cones and fin assemblies of other embodiments of the invention. The nose cone 450 may be constructed of three (3) or more substrate pieces 451 mated to neighboring substrate pieces, such as by the use of an adhesive. According to one implementation, the nose cone 450 is formed of one substrate piece. According to another implementation, the nose cone 450 is formed of two substrate pieces.

[0054]FIG. 10 illustrates the example of a tail assembly 410 according to the illustrated example of the third embodiment of the invention. The remaining aspects of the model rocket 400 according to the illustrated second embodiment may be similar to those described above in relation to the model rockets 200, 300 of the first and second embodiments. A tether 460 is illustrated and may be provided similar to the tether 260 illustrated in FIG. 3.

[0055] A wide variety of further configurations and variations are within the scope of the invention. For example, graphics may be provided on the substrate pieces forming the invention. Examples of graphics include differing numbers of windows reflecting various representative passenger capacities of the model rocket. Further options in colors and color intensities are also within the scope of the invention. Furthermore, variations in the shapes, sizes, angles and configurations of the components of the invention are within the scope of the invention. Examples include the locations, shapes and sizes, and inclusion or omission, of fuselage fins, nose cone fins, sweep angles and tail assembly fins.

[0056] In operation, the model rocket 200, 300, 400 according to the present invention may be propelled to substantial heights, as determined by the characteristics of the model rocket engine used. An electrical power source may be provided to ignite the model rocket engine, such as by the use of an igniter and igniter wadding or igniter holder. Because the present invention is adapted to be used with conventional model rocket engines, a wide variety of propulsion configurations will be apparent to one of skill in the art and are within the scope of the invention.

[0057] The tail assembly fins and any provided fuselage fins and/or nose cone fins may be configured to aerodynamically guide the model rocket throughout a flight, thereby allowing the model rocket to proceed along a generally consistent path. The model rocket according to the various embodiments of the invention is preferably configured to withstand a flight powered by a model rocket engine. The structure formed by the substrate forms a model rocket structural housing that may be independently strong enough to form components of the model rocket capable of withstanding the forces encountered by the rocket during a flight powered by a model rocket engine. By the use of folds in the substrate and/or mating of different substrate pieces together, additional structural strength is provided by the various components of the model rocket. By the selection of a suitably durable substrate, the model rocket may readily withstand one or more flights.

[0058] According to an implementation of the invention, the fuselage of the model rocket 200, 300, 400 has a non-cylindrical cross-section. According to another implementation of the invention, the fuselage of the model rocket 200, 300, 400 has a cylindrical cross-section.

[0059] As described in relation to the conventional model rocket 100, the flight of the model rocket according to the invention involves initial thrust lifting the model rocket. A delay stage may be included according to the characteristics of the model rocket used. According to one implementation of the invention, the model rocket engine will also provide an ejection charge, dislodging the nose cone 250, 350, 450 from the remainder of model rocket 200, 300, 400. The ejection charge may be configured to occur at or near the apogee of the flight of the model rocket, dislodging the nose cone 250, 350, 450 and optionally employing an additional means to control the descent of the model rocket in a variety of ways. For example, a tumble recovery of the model rocket may be performed using the dislodged nose cone itself. According to another implementation of the invention, a recovery device, such as a streamer 261, may be coupled to model rocket, such as by the tether 260, as illustrated in FIG. 3. The recovery device may be coupled to the fin assembly and/or the fuselage of the model rocket. Optionally, a second tether is used for the recovery device or the recovery device is mounted directly to the model rocket. As will be apparent to one of skill in the art, streamer 261, or a parachute or blades may be used with any of the embodiments of the present invention, and will function similarly to the recovery device 160 illustrated in conjunction with the conventional model rocket 100 of FIG. 1. Furthermore, a glider recovery may be performed, as described herein.

[0060] According to one implementation, the relationship between the center of gravity and center of pressure of the model rocket is changed by a shifting means near the apogee of the flight to enhance glider performance of the model rocket during the descent phase of the flight. The shifting means may change the relationship between the center of gravity and center of pressure by shifting the center of gravity or the center of pressure, or both. The center of gravity may be shifted in a variety of ways known in the art, such as by ejecting the model rocket engine using an ejection charge, or transferring weight along the model rocket. Weight can be shifted by the use of the ejection charge, a burn string, elastics and/or other devices known in the art.

[0061] A glider descent may also be performed by shifting the center of pressure of the model rocket, such as by shifting the position of the model rocket engine aft to extend the portion of the model rocket engine protruding from the fin assembly. The center of pressure can also be moved by shifting the position of fins. The ejection charge, a burn string, elastics and/or other devices known in the art, may be used to shift the model rocket engine or other parts of the model rocket forward or aft. According to one variation of this implementation of the invention, the tail assembly fins, fuselage fins and/or nose cone fins may be configured to enhance glider flight, such as by moving their position and/or forming an airfoil using a stiffener having a non-uniform thickness or by assembling one or more substrate pieces into an airfoil.

[0062] It is understood that a wide variety of shifting means and configurations enabling glider descent are within the scope of the invention. Further details can be found in Thomas E. Beach, TR-4 Boost Gliders Technical Report, Estes, 1995; Gordon Mandell, Estes Technical Report TR-4 Rear Engine Boost-Gliders, Estes, 1963; and Gordon Mandell, Estes Technical Report TR-7 Front Engine Boost-Gliders, Estes Industries, 1964.

[0063] According to a further variation of the invention, the nose cone 250, 350, 450 may be fixedly located to the remainder of model rocket 200, 300, 400, such as the fuselage and/or fin assembly. The nose cone 250, 350, 450 may be fixedly located to the remainder of model rocket in a variety of ways, such as by being an integral part of the fuselage, the use of adhesive and/or by tab and slot construction.

[0064] According to a further embodiment of the invention, a method of constructing a flyable model rocket 500 is provided as illustrated in FIG. 11. According to the method 500, a printer is instructed to print a model rocket structural housing on a substrate, step 510. The structural housing is then separated from the substrate, such as by cutting, step 520. The structural housing, which is configured to aerodynamically guide the model rocket and withstand a flight powered by a model rocket engine, is assembled, step 530. According to one implementation, the structural housing includes a nose cone removably mounted to tail assembly having a plurality of tail assembly fins.

[0065] According to another implementation of the invention, the method 500 may additionally include the mounting of an engine tube to the tail assembly of the structural housing, step 540. According to this implementation, a stiffener is located in each of the tail assembly fins, and has an engine retention tab extending inward within the tail assembly and located, step 550, to inhibit the engine from traveling through the tail assembly during flight of the model rocket. An example of such an engine retention tab 226 is shown in FIG. 4.

[0066] According to one implementation of the invention, the structural housing includes a fuselage mounted directly to the tail assembly and a nose cone removably mounted to the fuselage. According to this implementation, a further step of mounting an engine tube to the tail assembly of the structural housing may be provided, step 560. According to this implementation of the invention, the method 500 may optionally further include the step of locating a stiffener in each of the tail assembly fins, step 570. Each stiffener may have an engine retention tab extending inward within the tail assembly, the engine retention tab is located to inhibit the engine from traveling through the tail assembly during flight of the model rocket.

[0067] According to a further implementation of the invention, as illustrated in FIG. 11, the method 500 may optionally include a preliminary step of receiving instructions specifying characteristics of the model rocket, step 580. Although the invention is not so limited, examples of characteristics that may be specified include the fin quantity and fin sweep angle, size of the model rocket, shapes and sizes of noses, bodies and fins. Further characteristics may be reflected in the graphics printed on the substrate, such as the color, color intensity, decals, numbering, payload and passenger capacity. Payload and passenger capacity may be represented by numbers of windows or port holes printed on the substrate. A further graphical characteristic indicates the material of which the rocket is formed, as represented by the model rocket. For example, the model rocket may be intended to be a model of an aluminum, titanium or composite rocket.

[0068] According to a further implementation of the invention, the method 500 may include the step of displaying the model rocket, or components thereof, on a computer display, step 590. A further implementation of the invention includes the additional step of determining estimated parameters of the flight of the model rocket by the use of a computer, step 595. Although the invention is not so limited, examples of parameters that may be estimated include weight, drag, maximum altitude of flight, center of pressure, and center of gravity with regard to the stability of the rocket and the duration of the flight of the model rocket. According to a further implementation, wind speed and direction may be incorporated in various calculations.

[0069] According to a further embodiment of the invention, as illustrated by way of example in FIG. 12, a computer readable medium 600 is provided holding computer executable steps 610 for the various methods of the invention. In one implementation of the invention, the computer readable medium holds computer executable steps for a method including the steps of receiving instructions specifying characteristics of a model rocket and instructing a printer to print a model rocket structural housing on a substrate. According to this implementation of the invention, the structural housing is configured to aerodynamically guide the model rocket and withstand a flight powered by a model rocket engine. According to a variation of this implementation of the invention, the substrate is selected from a variety of papers, card stocks, thin plastic sheets, embossed stock, synthetic stock and adhesive-backed stock.

[0070] According to a further variation of this implementation of the invention, the method includes a further step of displaying the model rocket on a computer display after instructions specifying characteristics of the model rocket have been received.

[0071] According to various additional implementations of the invention, the instructions received specifying various characteristics of the model rocket involve characteristics including a fin sweep angle and/or a color intensity level.

[0072] According to a further implementation of the invention, a computer readable medium holding executable steps for a method includes a method having the additional step of determining estimated parameters of the flight of the model rocket and the center of pressure and center of gravity relationships of the model rocket by the use of a computer.

[0073] According to a further implementation of the invention, instructing step includes instructions to cause the printer to print a structural housing including components for a nose cone. In this implementation, the tail assembly may have a plurality of tail assembly fins.

[0074] According to a further implementation of the invention, the instructing step includes instructions to cause the printer to print a structural housing including components for a fuselage. A further variation of this implementation of the invention may include components for a fuselage with a non-cylindrical cross-section. According to another implementation of the invention, instructions are provided to cause the printer to print components for a fuselage having a cylindrical cross-section.

[0075] In a further implementation of the computer readable medium 600 an instructing step includes instructions to cause the printer to print a structural housing having components for a nose cone formed of at least three (3) substrate pieces, a fuselage that may be removably mounted to the nose cone, and a tail assembly fixedly mounted to the fuselage and formed of at least three (3) substrate pieces. In this implementation of the invention, a first substrate piece of the tail assembly and a second substrate piece of the tail assembly form a tail assembly fin at a location where the first and second substrate piece meet. Additional tail assembly fins may be similarly formed. Optionally, the nose cone and fuselage may each be formed of less than three (3) substrate pieces. It is understood that a wide variety of alternatives are available within the scope of the invention. For example, any of the variations discussed herein relating to the model rockets 200, 300, 400 may be implemented within the components of the structural housing.

[0076] According to a further implementation of the embodiment of the invention illustrated in FIG. 12, the structural housing may include components for a nose cone formed of four (4) substrate pieces. In such an implementation, the first substrate piece of the nose cone forms a nose cone fin at a location where the first and second substrate piece of the nose cone meet. Additional nose cone fins may be similarly formed. The structural housing further includes a fuselage, that may be designed to be removably mounted to the nose cone and a tail assembly formed of four (4) substrate pieces. In such an implementation, the first substrate piece of the tail assembly forms a tail assembly fin at a location where the first and second substrate pieces of the tail assembly meet. Additional tail assembly fins may be similarly formed. Optionally, the nose cone and fuselage may each be formed of less than four (4) substrate pieces.

[0077] According to a second embodiment of the computer readable medium 600 as illustrated in FIG. 12, the computer readable medium may include computer executable steps as follows. The computer executable step may include instructing a printer to print a model rocket structural housing on a substrate. According to this embodiment of the invention, the structural housing is configured to aerodynamically guide the model rocket and withstand a flight powered by a model rocket engine. According to a variation of this embodiment of the invention, the substrate is paper. According to further variations, examples of the substrate include a variety of papers, card stocks, thin plastic sheets, embossed stock, synthetic stock and adhesive-backed stock.

[0078] According to a further implementation of this embodiment of the invention, the instructing step may include instructions to cause the printer to print a structural housing including a nose cone that may be removably mounted directly to a tail assembly.

[0079] According to a further implementation of this embodiment of the invention, the instructing step includes instructions to cause the printer to print a structural housing including components for a fuselage adapted to be mounted directly to a tail assembly and a nose cone that may be removably mounted to the fuselage. A further variation of this implementation of the invention may include components for a fuselage with a non-cylindrical cross-section. According to another implementation of the invention, instructions are provided to cause the printer to print components for a fuselage having a cylindrical cross-section.

[0080] According to a further variation of this embodiment of the invention, the instructing step includes instructions to cause the printer to print a structural housing including components for a nose cone, formed of three substrate pieces, a fuselage, and a tail assembly. According to this implementation, the tail assembly is fixedly mounted to the fuselage and formed of three (3) substrate pieces, such that a first substrate piece of the tail assembly and a second substrate piece of the tail assembly form a tail assembly fin at a location where the first and second substrate piece meet.

[0081] According to a further implementation of this embodiment of the invention, the instructing step includes instructions to cause the printer to print a structural housing including components for a nose cone, formed of four substrate pieces, a fuselage, and a tail assembly. In this implementation, a first substrate piece of the nose cone forms a nose cone fin at a location where a first and second substrate piece meet. Also according to this implementation, the structural housing also includes a fuselage which can be removably mounted to the nose cone. Also included in the structural housing is a tail assembly formed of four (4) substrate pieces, such that a first substrate piece of the tail assembly forms a tail assembly fin at a location where the first and second substrate pieces of the tail assembly meet.

[0082] It is understood that further variations of the computer readable medium 600 of the present invention may include computer executable steps to instruct a printer to print a model rocket structural housing on a substrate according to any of the teachings of the invention as described herein.

[0083] According to another embodiment of the invention, as illustrated in FIG. 13, a flyable model rocket assembly kit 700 is provided. The kit includes a substrate 710 that is capable of accepting ink. The kit further includes software 720 holding computer executable instructions for instructing a printer to print a model rocket structural housing on the substrate. According to this embodiment of the invention, the structural housing is configured to aerodynamically guide the model rocket and withstand a flight powered by a model rocket engine. According to a variation of this embodiment of the invention, the flyable model rocket assembly kit 700 also includes ballast 730, such as modeling clay.

[0084] According to a further implementation of this embodiment of the invention, the structural housing printed by the printer that is instructed by the software 720 includes a nose cone formed of one or more substrate pieces. The structural housing further includes a fuselage, that may be removably mounted to the nose cone, and a tail assembly fixedly mounted to the fuselage and formed of one or more substrate pieces. According to an example implementation having three substrate pieces in each of the nose cone and fuselage, a first substrate piece of the tail assembly and a second substrate piece of the tail assembly form a tail assembly fin at a location where the substrate pieces meet. According to a variation of this implementation, the flyable model rocket assembly kit 700 further includes an engine tube 740 to be mounted in the tail assembly and a stiffener 750 to be located in each of the tail assembly fins. According to this implementation, the stiffener has an engine retention tab for extending inward within the tail assembly and inhibiting the engine from travelling through the tail assembly.

[0085] According to a further example implementation of this embodiment of the invention, the flyable model rocket assembly kit 700 includes software 720 configured to instruct a printer to print structural housing having a nose cone formed of four (4) substrate pieces. According to this implementation, a first substrate piece of the nose cone forms a nose cone fin at a location where the first substrate piece of the nose cone meets a second substrate piece of the nose cone. Also included in the structural housing of this implementation of the invention are a fuselage, that may be removably mounted to the nose cone, and a tail assembly formed of four (4) substrate pieces. In this implementation, a first substrate piece of the tail assembly forms a tail assembly fin at a location where the first substrate piece meets a second substrate piece of the tail assembly. According to a variation of this implementation, the flyable model rocket assembly kit 700 further includes an engine tube 740 to be mounted in the tail assembly. A stiffener 750 may also be included for locating in each of the tail assembly fins, such that the stiffener has an engine retention tab for extending inward within the tail assembly and inhibiting the engine from traveling through the tail assembly. A launch lug 760 may also be provided to assist in mounting the model rocket to launch equipment.

[0086] It is understood that further variations of the flyable model rocket assembly kit 700 of the present invention may include software to instruct a printer to print a model rocket structural housing on a substrate according to any of the teachings of the invention.

[0087] The various embodiments of the invention as described herein may be used in a variety of settings. For example, a teacher in a classroom setting may employ a flyable model rocket assembly kit that is sized to accommodate a classroom of students so as to enable the students in the classroom to each perform one or more of the methods of the invention or use one or more of the model rockets as described herein according to the invention. Such a kit is sufficiently sized by having sufficient supplies to provide each student the opportunity to design and construct their own model rocket. It is understood that in a classroom environment, the term “user,” as used herein, can include both a teacher and/or a student or students.

[0088] By way of a further example, the computer readable medium according to various embodiments of the invention may be made available to model rocket enthusiasts to enable the design and construction of personalized model rockets. According to one implementation, the computer readable medium according to the invention may be used by one or more users and may optionally be limited in the number of model rockets it will design and print. The model rockets of the invention may be combined with readily commercially available model rocket engines, and, optionally, engine tubes and other components. Furthermore, according to one implementation of the invention, the model rocket may be viewed on a computer display prior to printing or constructing the model rocket. Estimates may also be determined for the anticipated flight of the model rocket. By the use of one or more of the various aspects of the invention, the opportunity is provided for the model rocket enthusiast to interactively participate in the design aspects of the model rocket activity.

[0089] All documents or publications cited herein are incorporated in their entirety herein by reference. The present invention has been described by way of example, and modifications and variations of the described embodiments will suggest themselves to skilled artisans in this field without departing from the spirit of the invention. Aspects and characteristics of the above-described embodiments may be used in combination. The described embodiments are merely illustrative and should not be considered restrictive in any way. The scope of the invention is to be measured by the appended claims, rather than the preceding description, and all variations and equivalents that fall within the range of the claims are intended to be embraced therein. 

What is claimed is:
 1. A flyable model rocket, comprising: a nose cone formed of a printed substrate; and a tail assembly formed of a printed substrate and removably directly mated to said nose cone; wherein said tail assembly is adapted to be mounted to a model rocket engine.
 2. The flyable model rocket of claim 1, wherein a portion of said tail assembly fits into said nose cone.
 3. The flyable model rocket of claim 1, wherein said nose cone is formed with three mating slots and said tail assembly is formed with three tail assembly fins extending to interface with said mating slots.
 4. The flyable model rocket of claim 3, further comprising a stiffener for each of said tail assembly fins.
 5. The flyable model rocket of claim 4, wherein said stiffener is located in each of said tail assembly fins.
 6. The flyable model rocket of claim 1, wherein said printed substrate is selected from the group of paper and card stock.
 7. The flyable model rocket of claim 1, wherein said printed substrate is selected from the group of thin plastic sheets, embossed stock, synthetic stock and adhesive-backed stock.
 8. A flyable model rocket, comprising: a nose cone formed of three substrate pieces, wherein a first substrate piece of said nose cone forms a nose cone fin at a location where said first substrate piece of said nose cone meets a second substrate piece of said nose cone; and a tail assembly formed of three substrate pieces, wherein a first substrate piece of said tail assembly forms a tail assembly fin at a location where said first substrate piece of said tail assembly meets a second substrate piece of said nose cone.
 9. The flyable model rocket of claim 8, wherein said tail assembly fin is coupled with said nose cone fin.
 10. The flyable model rocket of claim 8, further comprising an engine tube fixedly mounted to said tail assembly such that said substrate pieces of said tail assembly extend along a portion of a circumference of said engine tube.
 11. The flyable model rocket of claim 10, further comprising a stiffener located in each of said tail assembly fins, wherein said stiffener has an engine retention tab extending inward within said tail assembly and located to inhibit said engine tube from travelling through said tail assembly.
 12. A flyable model rocket, comprising: a nose cone formed of a printed substrate; and a tail assembly formed of a printed substrate and fixedly directly mated to said nose cone; wherein said tail assembly is adapted to be mounted to a model rocket engine.
 13. The flyable model rocket of claim 12, wherein said printed substrate is selected from the group of paper and card stock.
 14. The flyable model rocket of claim 12, wherein said printed substrate is selected from the group of thin plastic sheets, embossed stock, synthetic stock and adhesive-backed stock.
 15. A flyable model rocket, comprising: a nose cone formed of at least one substrate piece; a fuselage mounted to said nose cone; and a tail assembly fixedly mounted to said fuselage and formed of at least two substrate pieces, wherein a first substrate piece of said tail assembly and a second substrate piece of said tail assembly form a tail assembly fin at a location where said first substrate piece of said tail assembly meets said second substrate piece of said tail assembly.
 16. The flyable model rocket of claim 15, further comprising a fuselage fin on said fuselage.
 17. The flyable model rocket of claim 15, wherein said nose cone, fuselage and tail assembly are configured to aerodynamically guide said model rocket and withstand a flight powered by a model rocket engine.
 18. The flyable model rocket of claim 17, wherein said nose cone is removably mounted to said fuselage and coupled to said fuselage by a tether.
 19. The flyable model rocket of claim 18, wherein said nose cone is adapted to be detached from said fuselage near an apogee of a flight to enable a tumbling descent of said flyable model rocket.
 20. The flyable model rocket of claim 15, wherein said fuselage is formed of at least one substrate piece.
 21. The flyable model rocket of claim 20, wherein said at least one substrate piece of said fuselage is folded.
 22. The flyable model rocket of claim 15, further comprising: a recovery device coupled to said model rocket and selected from the group of a streamer, a parachute and rotating blades; wherein said nose cone is adapted to be detached from said fuselage near an apogee of a flight to enable deployment of said recovery device and a controlled descent of said flyable model rocket by the use of said recovery device.
 23. The flyable model rocket of claim 15, further comprising a shifting means to shift at least one of the group of the center of pressure and the center of gravity of the flyable model rocket near an apogee of a flight to enable a glider descent of said flyable model rocket.
 24. The flyable model rocket of claim 15, further comprising an engine tube fixedly mounted to said tail assembly such that said substrate pieces of said tail assembly extend along a portion of a circumference of said engine tube.
 25. The flyable model rocket of claim 24, further comprising a stiffener for each of said tail assembly fins.
 26. The flyable model rocket of claim 25, further comprising a stiffener located in each of said tail assembly fins, wherein said stiffener has an engine retention tab extending inward within said tail assembly and located to inhibit said engine tube from travelling through said tail assembly.
 27. The flyable model rocket of claim 15, wherein said nose cone is formed of three substrate pieces and said tail assembly has three tail assembly fins.
 28. The flyable model rocket of claim 15, wherein said nose cone is formed of four substrate pieces and said tail assembly has four tail assembly fins.
 29. The flyable model rocket of claim 15, wherein said substrate pieces are selected from the group of paper and card stock.
 30. The flyable model rocket of claim 15, wherein said substrate pieces are selected from the group of thin plastic sheets, embossed stock, synthetic stock and adhesive-backed stock.
 31. The flyable model rocket of claim 15, wherein said nose cone is fixedly mounted to said fuselage.
 32. A flyable model rocket, comprising: a fuselage formed of at least one printed substrate piece; and a tail assembly fixedly mounted to said fuselage and formed of at least two substrate pieces, wherein a first substrate piece of said tail assembly and a second substrate piece of said tail assembly form a tail assembly fin at a location where said first substrate piece of said tail assembly meets said second substrate piece of said tail assembly.
 33. The flyable model rocket of claim 32, further comprising a nose cone mounted to said fuselage.
 34. The flyable model rocket of claim 32, wherein said nose cone is manufactured from a material selected from the group of wood, plastic or fiberglass.
 35. The flyable model rocket of claim 34, wherein said nose cone is removably mounted to said fuselage.
 36. A flyable model rocket, comprising: a nose cone formed of at least two substrate pieces, wherein a first substrate piece of said nose cone forms a nose cone fin at a location where said first substrate piece of said nose cone meets a second substrate piece of said nose cone; a fuselage mounted to said nose cone; and a tail assembly formed of at least two substrate pieces, wherein a first substrate piece of said tail assembly forms a tail assembly fin at a location where said first substrate piece of said tail assembly meets a second substrate piece of said tail assembly.
 37. The flyable model rocket of claim 36, further comprising a fuselage fin integral to said fuselage.
 38. The flyable model rocket of claim 36, wherein said nose cone, fuselage and tail assembly are configured to aerodynamically guide said model rocket and withstand a flight powered by a model rocket engine.
 39. The flyable model rocket of claim 36, wherein said fuselage is formed of at least one substrate piece.
 40. The flyable model rocket of claim 39, wherein said at least one substrate piece of said fuselage is folded.
 41. The flyable model rocket of claim 36, wherein said nose cone is removably mounted to said fuselage and coupled to said fuselage by a tether.
 42. The flyable model rocket of claim 41, wherein said nose cone is adapted to be detached from said fuselage near an apogee of a flight to enable a tumbling descent of said flyable model rocket.
 43. The flyable model rocket of claim 36, further comprising: a recovery device coupled to said model rocket and selected from the group of a streamer, a parachute and rotating blades; wherein said nose cone is adapted to be detached from said fuselage near an apogee of a flight to enable deployment of said recovery device and a controlled descent of said flyable model rocket by the use of said recovery device.
 44. The flyable model rocket of claim 36, further comprising a shifting means to shift at least one of the group of the center of pressure and the center of gravity of the flyable model rocket near an apogee of a flight to enable a glider descent of said flyable model rocket.
 45. The flyable model rocket of claim 36, further comprising an engine tube fixedly mounted to said tail assembly such that said substrate pieces of said tail assembly extend along a portion of a circumference of said engine tube.
 46. The flyable model rocket of claim 45, further comprising a stiffener located in each of said tail assembly fins, wherein said stiffener has an engine retention tab extending inward within said tail assembly and located to inhibit said engine tube from travelling through said tail assembly.
 47. The flyable model rocket of claim 36, wherein said nose cone is formed of three substrate pieces and said tail assembly has three tail assembly fins.
 48. The flyable model rocket of claim 36, wherein said nose cone is formed of four substrate pieces and said tail assembly has four tail assembly fins.
 49. The flyable model rocket of claim 36, wherein said nose cone is fixedly mounted to said fuselage.
 50. A method for constructing a flyable model rocket, comprising the steps of: instructing a printer to print a model rocket structural housing on a substrate; separating said structural housing from a remainder of said substrate; and assembling said structural housing; wherein said structural housing is configured to aerodynamically guide said model rocket and withstand a flight powered by a model rocket engine.
 51. The method of claim 50, wherein said separating step is performed by cutting of said substrate by a user of the model rocket.
 52. The method of claim 50, wherein said assembling step includes assembling a structural housing having a nose cone removably mounted directly to a tail assembly having a plurality of tail assembly fins.
 53. The method of claim 52, further comprising the step of providing a stiffener for each of said tail assembly fins.
 54. The method of claim 52, further comprising the steps of: mounting an engine tube to said tail assembly of said structural housing; and locating a stiffener in each of said tail assembly fins, wherein said stiffener has an engine retention tab extending inward within said tail assembly and is located to inhibit said engine tube from travelling through said tail assembly during said flight.
 55. The method of claim 50, wherein said assembling step includes assembling a structural housing having a fuselage mounted directly to a tail assembly and a nose cone removably mounted to said fuselage.
 56. The method of claim 55, further comprising the step of mounting an engine tube to said tail assembly of said structural housing.
 57. The method of claim 56, further comprising the step of locating a stiffener in each of said tail assembly fins, wherein said stiffener has an engine retention tab extending inward within said tail assembly and located to inhibit said engine from travelling through said tail assembly during said flight.
 58. The method of claim 55, wherein said assembling step includes assembling a structural housing with said fuselage having a non-cylindrical cross-section.
 59. The method of claim 50, further comprising, before said instructing step, the step of receiving instructions specifying characteristics of said model rocket.
 60. The method of claim 50, further comprising the step of displaying said model rocket on a computer display.
 61. The method of claim 50, further comprising the step of determining estimated parameters of said flight by the use of a computer.
 62. The method of claim 50, further comprising the step of determining estimated parameters of said flight by the use of a computer, wherein said estimated parameters include at least one of a center of pressure of said model rocket and a center of gravity of said model rocket.
 63. A computer readable medium holding computer-executable steps for a method comprising the steps of: receiving instructions specifying characteristics of a flyable model rocket; and instructing a printer to print a model rocket structural housing on a substrate; wherein said structural housing is configured to aerodynamically guide said flyable model rocket and withstand a flight powered by a model rocket engine.
 64. The computer readable medium of claim 63, wherein said instructing step includes instructions to cause said printer to print on a paper substrate.
 65. The computer readable medium of claim 63, wherein said instructing step includes instructions to cause said printer to print on a substrate selected from the group of paper and card stock.
 66. The computer readable medium of claim 63, wherein said instructing step includes instructions to cause said printer to print on a substrate selected from the group of thin plastic sheets, embossed stock, synthetic stock and adhesive-backed stock.
 67. The computer readable medium of claim 63, wherein said method further comprises the step of displaying said model rocket on a computer display.
 68. The computer readable medium of claim 63, wherein said receiving step includes receiving characteristics including a fin sweep angle.
 69. The computer readable medium of claim 63, wherein said receiving step includes receiving characteristics including a color intensity level.
 70. The computer readable medium of claim 63, wherein said method further comprises the step of determining estimated parameters of said flight by the use of a computer.
 71. The computer readable medium of claim 63, wherein said method further comprises the step of determining estimated parameters of said flight by the use of a computer, wherein said estimated parameters include at least one of a center of pressure of said model rocket and a center of gravity of said model rocket.
 72. The computer readable medium of claim 63, wherein said instructing step includes instructions to cause said printer to print a structural housing including components for a nose cone.
 73. The computer readable medium of claim 63, wherein said instructing step includes instructions to cause said printer to print a structural housing including components for a fuselage.
 74. The computer readable medium of claim 63, wherein said instructing step includes instructions to cause said printer to print a structural housing including components for a fuselage with a non-cylindrical cross-section.
 75. The computer readable medium of claim 63, wherein said instructing step includes instructions to cause said printer to print a structural housing including components for: a nose cone formed of less than three substrate pieces; a fuselage; and a tail assembly formed of less than three substrate pieces and having at least one tail assembly fin, wherein a first substrate piece of said tail assembly and a second substrate piece of said tail assembly are adapted to form said at least one tail assembly fin.
 76. The computer readable medium of claim 63, wherein said instructing step includes instructions to cause said printer to print a structural housing including components for: a nose cone formed of three substrate pieces; a fuselage; and a tail assembly formed of three substrate pieces and having three tail assembly fins, wherein a first substrate piece of said tail assembly and a second substrate piece of said tail assembly are adapted to form one of said tail assembly fins.
 77. The computer readable medium of claim 63, wherein said instructing step includes instructions to cause said printer to print a structural housing including components for: a nose cone formed of four substrate pieces, wherein a first substrate piece of said nose cone forms a nose cone fin; a fuselage; and a tail assembly formed of four substrate pieces and having four fin assembly fins, wherein a first substrate piece of said tail assembly and a second substrate piece of said tail assembly are adapted to form one of said tail assembly fins.
 78. A computer readable medium holding computer-executable steps for instructing a printer to print a model rocket structural housing on a substrate, such that said structural housing is configured to aerodynamically guide said model rocket and withstand a flight powered by a model rocket engine.
 79. The computer readable medium of claim 78, wherein said instructing step includes instructions to cause said printer to print on a paper substrate.
 80. The computer readable medium of claim 78, wherein said instructing step includes instructions to cause said printer to print on a substrate selected from the group of paper and card stock.
 81. The computer readable medium of claim 78, wherein said instructing step includes instructions to cause said printer to print on a substrate selected from the group of thin plastic sheets, embossed stock, synthetic stock and adhesive-backed stock.
 82. The computer readable medium of claim 78, wherein said instructing step includes instructions to cause said printer to print a structural housing including components for a nose cone adapted to be removably mounted directly to a tail assembly.
 83. The computer readable medium of claim 78, wherein said instructing step includes instructions to cause said printer to print a structural housing including components for a fuselage adapted to be mounted directly to a tail assembly and a nose cone removably mounted to said fuselage.
 84. The computer readable medium of claim 83, wherein said instructing step includes instructions to cause said printer to print a structural housing including components for a fuselage having a non-cylindrical cross-section.
 85. The computer readable medium of claim 78, wherein said instructing step includes instructions to cause said printer to print a structural housing including components for: a nose cone formed of three substrate pieces; a fuselage, adapted to be removably mounted to said nose cone; and a tail assembly adapted to be fixedly mounted to said fuselage and formed of three substrate pieces, wherein a first substrate piece of said tail assembly and a second substrate piece of said tail assembly are adapted to form a tail assembly fin at a location where said first substrate piece of said tail assembly meets said second substrate piece of said tail assembly.
 86. The computer readable medium of claim 78, wherein said instructing step includes instructions to cause said printer to print a structural housing including components for: a nose cone formed of four substrate pieces, wherein a first substrate piece of said nose cone is adapted to form a nose cone fin at a location where said first substrate piece of said nose cone meets a second substrate piece of said nose cone; a fuselage, adapted to be removably mounted to said nose cone; and a tail assembly formed of four substrate pieces and having four fin assembly fins, wherein a first substrate piece of said tail assembly and a second substrate piece of said tail assembly are adapted to form one of said tail assembly fins at a location where said first substrate piece of said tail assembly meets said second substrate piece of said tail assembly.
 87. A flyable model rocket assembly kit, comprising: a substrate capable of accepting ink; and software holding computer-executable steps for instructing a printer to print a model rocket structural housing on said substrate; wherein said structural housing can be configured to aerodynamically guide said model rocket and withstand a flight powered by a model rocket engine.
 88. The flyable model rocket assembly kit of claim 87, further comprising ballast to be mounted in said structural housing to locate a center of gravity of the model rocket ahead of a center of pressure occurring during said flight.
 89. The flyable model rocket assembly kit of claim 87, wherein said software is configured to instruct a printer to print a structural housing comprising: a nose cone formed of three substrate pieces; a fuselage; and a tail assembly formed of three substrate pieces, wherein a first substrate piece of said tail assembly and a second substrate piece of said tail assembly adapted to form a tail assembly fin.
 90. The flyable model rocket assembly kit of claim 89, further comprising: an engine tube to be mounted in said tail assembly; and a stiffener for each of said tail assembly fins.
 91. The flyable model rocket assembly kit of claim 90, wherein said stiffener has an engine retention tab for extending inward within said tail assembly and inhibiting said engine from travelling through said tail assembly.
 92. The flyable model rocket assembly kit of claim 87, wherein said software is configured to instruct a printer to print a structural housing comprising: a nose cone formed of four substrate pieces, wherein a first substrate piece of said nose cone forms a nose cone fin; a fuselage; and a tail assembly formed of four substrate pieces and having four fin assembly fins, wherein a first substrate piece of said tail assembly and a second substrate piece of said tail assembly are adapted to form one of said tail assembly fins.
 93. The flyable model rocket assembly kit of claim 91, further comprising: an engine tube to be mounted in said tail assembly; and a stiffener for each of said tail assembly fins.
 94. The flyable model rocket assembly kit of claim 93, wherein said stiffener has an engine retention tab for extending inward within said tail assembly and inhibiting said engine from travelling through said tail assembly.
 95. The flyable model rocket of claim 87, wherein said substrate is selected from the group of paper and card stock.
 96. The flyable model rocket of claim 87, wherein said substrate is selected from the group of thin plastic sheets, embossed stock, synthetic stock and adhesive-backed stock. 